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重要：

在Java中不带模式和填充来获取AES算法的时候，其默认使用AES/ECB/PKCS5Padding！！！

1 Java的AES加解密

如果把Cipher.getInstance(“AES”);中的”AES”换成”AES/ECB/PKCS5Padding”，效果是一样的。

1.1 加密操作
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/**
   * Description: 加密操作 <br>
   *
   * @param data 待加密数据
   * @param key  密钥
   * @return 加解密后的信息
   * @throws Exception <br>
   */
  public static byte[] encrypt(byte[] data, byte[] key)
          throws Exception {
      Key secretKey = new SecretKeySpec(key, "AES");
      Cipher cipher = Cipher.getInstance("AES");
      cipher.init(Cipher.ENCRYPT_MODE, secretKey);
      return cipher.doFinal(data);
  }

1.2 解密操作

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/**
 * Description: 解密操作 <br>
 *
 * @param data 待解密数据
 * @param key  密钥
 * @return 解密后的信息
 * @throws Exception <br>
 */
public static byte[] decrypt(byte[] data, byte[] key)
        throws Exception {
    Key secretKey = new SecretKeySpec(key, "AES");
    Cipher cipher = Cipher.getInstance("AES");
    cipher.init(Cipher.DECRYPT_MODE, secretKey);
    return cipher.doFinal(data);
}

2 Golang的AES加解密

Golang中是没有现成的ECB/PKCS5Padding填充算法的，需要自己写或找份。

2.1 加密操作
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//ECB PKCS5 加密
func AESEncrypt(src, key []byte) []byte {
	block, err := aes.NewCipher(key)
	if err != nil {
		log.Logger.Error("txn put fail: %v", err)
		return nil
	}
	ecb := NewECBEncrypter(block)
	content := []byte(src)
	content = PKCS5Padding(content, block.BlockSize())
	des := make([]byte, len(content))
	ecb.CryptBlocks(des, content)
	return des
}
2.2 解密操作
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//ECB PKCS5 解密
func AesDecrypt(crypted, key []byte) []byte {
	block, err := aes.NewCipher(key)
	if err != nil {
		log.Logger.Error("txn get fail: %v", err)
		return nil
	}
	blockMode := NewECBDecrypter(block)
	origData := make([]byte, len(crypted))
	blockMode.CryptBlocks(origData, crypted)
	origData = PKCS5UnPadding(origData)
	return origData
}

2.3 PKCS5Padding
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//PKCS5Padding
func PKCS5Padding(ciphertext []byte, blockSize int) []byte {
	padding := blockSize - len(ciphertext)%blockSize
	padtext := bytes.Repeat([]byte{byte(padding)}, padding)
	return append(ciphertext, padtext...)
}
2.4 PKCS5UnPadding
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//PKCS5UnPadding
func PKCS5UnPadding(origData []byte) []byte {
	length := len(origData)
	// 去掉最后一个字节 unpadding 次
	unpadding := int(origData[length-1])
	return origData[:(length - unpadding)]
}

2.5 ECB
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package ecb

import "crypto/cipher"

type ecb struct {
	b         cipher.Block
	blockSize int
}

func newECB(b cipher.Block) *ecb {
	return &ecb{
		b:         b,
		blockSize: b.BlockSize(),
	}
}

type ecbEncrypter ecb

// NewECBEncrypter returns a BlockMode which encrypts in electronic code book
// mode, using the given Block.
func NewECBEncrypter(b cipher.Block) cipher.BlockMode {
	return (*ecbEncrypter)(newECB(b))
}
func (x *ecbEncrypter) BlockSize() int { return x.blockSize }
func (x *ecbEncrypter) CryptBlocks(dst, src []byte) {
	if len(src)%x.blockSize != 0 {
		panic("crypto/cipher: input not full blocks")
	}
	if len(dst) < len(src) {
		panic("crypto/cipher: output smaller than input")
	}
	for len(src) > 0 {
		x.b.Encrypt(dst, src[:x.blockSize])
		src = src[x.blockSize:]
		dst = dst[x.blockSize:]
	}
}

type ecbDecrypter ecb

// NewECBDecrypter returns a BlockMode which decrypts in electronic code book
// mode, using the given Block.
func NewECBDecrypter(b cipher.Block) cipher.BlockMode {
	return (*ecbDecrypter)(newECB(b))
}
func (x *ecbDecrypter) BlockSize() int { return x.blockSize }
func (x *ecbDecrypter) CryptBlocks(dst, src []byte) {
	if len(src)%x.blockSize != 0 {
		panic("crypto/cipher: input not full blocks")
	}
	if len(dst) < len(src) {
		panic("crypto/cipher: output smaller than input")
	}
	for len(src) > 0 {
		x.b.Decrypt(dst, src[:x.blockSize])
		src = src[x.blockSize:]
		dst = dst[x.blockSize:]
	}
}

参考资料

golang AES/ECB/PKCS5 加密解密 url-safe-base64
aes加密解密，含 128、192、256位，cbc、cfb、ecb、ofb、pcbc模式

感谢网络上的大神！